Traditionally, vehicles include multiple systems that regulate overall operation of the vehicle. For example, the vehicle includes a power plant (e.g., an internal combustion engine and/or an electric machine) that generates drive torque, an energy storage device (e.g., battery pack) that provides electrical energy, a transmission that distributes the drive torque to drive wheels and various other systems. Each of the systems includes an associated control modules or modules that communicate with one another to regulate operation of the vehicle.
Modern vehicles include an on-board diagnostic (OBD) system that provides almost complete engine control and also monitors the vehicle systems, as well as the diagnostic control network of the vehicle. The OBD system checks proper operation of the various control modules of the vehicle systems, as well as sensors (e.g., pre and post catalyst oxygen sensors) and other components. If there is a fault with any of the components, a malfunction indicator lamp (MIL) is illuminated and a diagnostic trouble code (DTC) is set. A vehicle technician or owner can readily determine the source of the fault by connecting a generic service tool to an OBD port located on the vehicle, which reads the DTC.
With the advent of more complex vehicle systems, such as hybrid electric vehicles, the number of inter-linked control modules increases. As a result, the coordination of the OBD required diagnostics of the individual control modules increases. Accordingly, OBD systems are tailored to the unique systems of a particular vehicle, which requires time, effort and cost per each vehicle platform. Presently, there is not a common OBD system approach that is readily adaptable to vehicle with varying system configurations.